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    <title>Magnify</title>
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        This example uses OpenLayers v<span>4.4.2</span>. The <a id="latest-link" href="#" class="alert-link">latest</a> is v<span id="latest-version"></span>.
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          <h4 id="title">Magnify</h4>
          <div id="map" class="map"></div>

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        <div class="span12">
          <p id="shortdesc">Show a magnified version of imager under the pointer</p>
          <div id="docs"><p>This example makes use of the <code>postcompose</code> event listener to oversample imagery in a circle around the pointer location.  Listeners for this event have access to the Canvas context and can manipulate image data.</p> <p>Move around the map to see the effect.  Use the ↑ up and ↓ down arrow keys to adjust the magnified circle size.</p>
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          <div id="api-links">Related API documentation: <ul class="inline"><li><a href="../apidoc/ol.Map.html" title="API documentation for ol.Map">ol.Map</a></li>,<li><a href="../apidoc/ol.View.html" title="API documentation for ol.View">ol.View</a></li>,<li><a href="../apidoc/ol.layer.Tile.html" title="API documentation for ol.layer.Tile">ol.layer.Tile</a></li>,<li><a href="../apidoc/ol.proj.html" title="API documentation for ol.proj">ol.proj</a></li>,<li><a href="../apidoc/ol.source.BingMaps.html" title="API documentation for ol.source.BingMaps">ol.source.BingMaps</a></li></ul></div>
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          <a id="codepen-button"><i class="fa fa-codepen"></i> Edit</a>
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        <form method="POST" id="codepen-form" target="_blank" action="https://codepen.io/pen/define/">
          <textarea class="hidden" name="title">Magnify</textarea>
          <textarea class="hidden" name="description">Show a magnified version of imager under the pointer</textarea>
          <textarea class="hidden" name="js">var key &#x3D; &#x27;Your Bing Maps Key from http://www.bingmapsportal.com/ here&#x27;;

var imagery &#x3D; new ol.layer.Tile({
  source: new ol.source.BingMaps({key: key, imagerySet: &#x27;Aerial&#x27;})
});

var container &#x3D; document.getElementById(&#x27;map&#x27;);

var map &#x3D; new ol.Map({
  layers: [imagery],
  target: container,
  view: new ol.View({
    center: ol.proj.fromLonLat([-109, 46.5]),
    zoom: 6
  })
});

var radius &#x3D; 75;
document.addEventListener(&#x27;keydown&#x27;, function(evt) {
  if (evt.which &#x3D;&#x3D;&#x3D; 38) {
    radius &#x3D; Math.min(radius + 5, 150);
    map.render();
    evt.preventDefault();
  } else if (evt.which &#x3D;&#x3D;&#x3D; 40) {
    radius &#x3D; Math.max(radius - 5, 25);
    map.render();
    evt.preventDefault();
  }
});

// get the pixel position with every move
var mousePosition &#x3D; null;

container.addEventListener(&#x27;mousemove&#x27;, function(event) {
  mousePosition &#x3D; map.getEventPixel(event);
  map.render();
});

container.addEventListener(&#x27;mouseout&#x27;, function() {
  mousePosition &#x3D; null;
  map.render();
});

// after rendering the layer, show an oversampled version around the pointer
imagery.on(&#x27;postcompose&#x27;, function(event) {
  if (mousePosition) {
    var context &#x3D; event.context;
    var pixelRatio &#x3D; event.frameState.pixelRatio;
    var half &#x3D; radius * pixelRatio;
    var centerX &#x3D; mousePosition[0] * pixelRatio;
    var centerY &#x3D; mousePosition[1] * pixelRatio;
    var originX &#x3D; centerX - half;
    var originY &#x3D; centerY - half;
    var size &#x3D; 2 * half + 1;
    var sourceData &#x3D; context.getImageData(originX, originY, size, size).data;
    var dest &#x3D; context.createImageData(size, size);
    var destData &#x3D; dest.data;
    for (var j &#x3D; 0; j &lt; size; ++j) {
      for (var i &#x3D; 0; i &lt; size; ++i) {
        var dI &#x3D; i - half;
        var dJ &#x3D; j - half;
        var dist &#x3D; Math.sqrt(dI * dI + dJ * dJ);
        var sourceI &#x3D; i;
        var sourceJ &#x3D; j;
        if (dist &lt; half) {
          sourceI &#x3D; Math.round(half + dI / 2);
          sourceJ &#x3D; Math.round(half + dJ / 2);
        }
        var destOffset &#x3D; (j * size + i) * 4;
        var sourceOffset &#x3D; (sourceJ * size + sourceI) * 4;
        destData[destOffset] &#x3D; sourceData[sourceOffset];
        destData[destOffset + 1] &#x3D; sourceData[sourceOffset + 1];
        destData[destOffset + 2] &#x3D; sourceData[sourceOffset + 2];
        destData[destOffset + 3] &#x3D; sourceData[sourceOffset + 3];
      }
    }
    context.beginPath();
    context.arc(centerX, centerY, half, 0, 2 * Math.PI);
    context.lineWidth &#x3D; 3 * pixelRatio;
    context.strokeStyle &#x3D; &#x27;rgba(255,255,255,0.5)&#x27;;
    context.putImageData(dest, originX, originY);
    context.stroke();
    context.restore();
  }
});
</textarea>
          <textarea class="hidden" name="css"></textarea>
          <textarea class="hidden" name="html">&lt;div id&#x3D;&quot;map&quot; class&#x3D;&quot;map&quot;&gt;&lt;/div&gt;
</textarea>
          <input type="hidden" name="resources" value="https://openlayers.org/en/v4.4.2/css/ol.css,https://openlayers.org/en/v4.4.2/build/ol.js">
          <input type="hidden" name="data">
        </form>
        <pre><code id="example-source" class="language-markup">&lt;!DOCTYPE html&gt;
&lt;html&gt;
  &lt;head&gt;
    &lt;title&gt;Magnify&lt;/title&gt;
    &lt;link rel="stylesheet" href="https://openlayers.org/en/v4.4.2/css/ol.css" type="text/css"&gt;
    &lt;!-- The line below is only needed for old environments like Internet Explorer and Android 4.x --&gt;
    &lt;script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"&gt;&lt;/script&gt;
    &lt;script src="https://openlayers.org/en/v4.4.2/build/ol.js"&gt;&lt;/script&gt;
  &lt;/head&gt;
  &lt;body&gt;
    &lt;div id&#x3D;&quot;map&quot; class&#x3D;&quot;map&quot;&gt;&lt;/div&gt;
    &lt;script&gt;
      var key &#x3D; &#x27;Your Bing Maps Key from http://www.bingmapsportal.com/ here&#x27;;

      var imagery &#x3D; new ol.layer.Tile({
        source: new ol.source.BingMaps({key: key, imagerySet: &#x27;Aerial&#x27;})
      });

      var container &#x3D; document.getElementById(&#x27;map&#x27;);

      var map &#x3D; new ol.Map({
        layers: [imagery],
        target: container,
        view: new ol.View({
          center: ol.proj.fromLonLat([-109, 46.5]),
          zoom: 6
        })
      });

      var radius &#x3D; 75;
      document.addEventListener(&#x27;keydown&#x27;, function(evt) {
        if (evt.which &#x3D;&#x3D;&#x3D; 38) {
          radius &#x3D; Math.min(radius + 5, 150);
          map.render();
          evt.preventDefault();
        } else if (evt.which &#x3D;&#x3D;&#x3D; 40) {
          radius &#x3D; Math.max(radius - 5, 25);
          map.render();
          evt.preventDefault();
        }
      });

      // get the pixel position with every move
      var mousePosition &#x3D; null;

      container.addEventListener(&#x27;mousemove&#x27;, function(event) {
        mousePosition &#x3D; map.getEventPixel(event);
        map.render();
      });

      container.addEventListener(&#x27;mouseout&#x27;, function() {
        mousePosition &#x3D; null;
        map.render();
      });

      // after rendering the layer, show an oversampled version around the pointer
      imagery.on(&#x27;postcompose&#x27;, function(event) {
        if (mousePosition) {
          var context &#x3D; event.context;
          var pixelRatio &#x3D; event.frameState.pixelRatio;
          var half &#x3D; radius * pixelRatio;
          var centerX &#x3D; mousePosition[0] * pixelRatio;
          var centerY &#x3D; mousePosition[1] * pixelRatio;
          var originX &#x3D; centerX - half;
          var originY &#x3D; centerY - half;
          var size &#x3D; 2 * half + 1;
          var sourceData &#x3D; context.getImageData(originX, originY, size, size).data;
          var dest &#x3D; context.createImageData(size, size);
          var destData &#x3D; dest.data;
          for (var j &#x3D; 0; j &lt; size; ++j) {
            for (var i &#x3D; 0; i &lt; size; ++i) {
              var dI &#x3D; i - half;
              var dJ &#x3D; j - half;
              var dist &#x3D; Math.sqrt(dI * dI + dJ * dJ);
              var sourceI &#x3D; i;
              var sourceJ &#x3D; j;
              if (dist &lt; half) {
                sourceI &#x3D; Math.round(half + dI / 2);
                sourceJ &#x3D; Math.round(half + dJ / 2);
              }
              var destOffset &#x3D; (j * size + i) * 4;
              var sourceOffset &#x3D; (sourceJ * size + sourceI) * 4;
              destData[destOffset] &#x3D; sourceData[sourceOffset];
              destData[destOffset + 1] &#x3D; sourceData[sourceOffset + 1];
              destData[destOffset + 2] &#x3D; sourceData[sourceOffset + 2];
              destData[destOffset + 3] &#x3D; sourceData[sourceOffset + 3];
            }
          }
          context.beginPath();
          context.arc(centerX, centerY, half, 0, 2 * Math.PI);
          context.lineWidth &#x3D; 3 * pixelRatio;
          context.strokeStyle &#x3D; &#x27;rgba(255,255,255,0.5)&#x27;;
          context.putImageData(dest, originX, originY);
          context.stroke();
          context.restore();
        }
      });
    &lt;/script&gt;
  &lt;/body&gt;
&lt;/html&gt;</code></pre>
      </div>
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    <script src="./resources/prism/prism.min.js"></script>
    <script src="loader.js?id=magnify"></script>
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  fetch(packageUrl).then(function(response) {
    return response.json();
  }).then(function(json) {
    var latestVersion = json.version;
    document.getElementById('latest-version').innerHTML = latestVersion;
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    if (!dismissed && /^v[0-9\.]*$/.test(branchSearch[1]) && '4.4.2' != latestVersion) {
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